The Australians completed the comeback in extra time to earn their first Challengers Stage victory.

Grayhound pulled off the upset over Cloud9 in their 0-1 match, sending the Russians to the elimination pool of the IEM Rio Major Challengers Stage. The Australians were down 5-10 by halftime, but found their groove and turned things around for a 19-17 overtime win. Vladislav "⁠nafany⁠" Gorshkov's side now require a flawless display in their next three matches if they want to reach the next stage of the tournament, with a loss immediately eliminating them from the Major.

Meanwhile in the 1-0 pool, fnatic handed OG their first loss in Rio after taking home a 16-13 victory on Mirage. William "⁠mezii⁠" Merriman's squad join Bad News Eagles, GamerLegion, and MOUZ on the list of teams who went undefeated on day one, with the quartet now just one series away from progressing through to the Legends Stage.

Cloud9 opened Dust2 with a 4-0 lead behind Abay "⁠HObbit⁠" Khassenov's hot hand with eight kills. Grayhound finally got themselves on the board in the fifth, but couldn't quite shake the Russians as nafany and company remained comfortably ahead and finished the half with a 10-5 advantage. HObbit and Dmitry "⁠sh1ro⁠" Sokolov were the heaviest hitters throughout the first half and went into the switch with 20 and 16 kills, respectively.

Grayhound turned the game on its head in the second period as they won six straight coming out of halftime, a spree which completely erased their deficit and gave them an 11-10 lead. The Australians later clinched match point at 15-13, but Cloud9 dug deep and scored the last two rounds of regulation through successful A pushes to force overtime. Six rounds of extra time later, Joshua "⁠INS⁠" Potter's men completed their second half comeback and emerged victorious over Cloud9, 19-17.

sh1ro and HObbit's had a performance for the books with 36 and 34 kills each, but their efforts weren't enough to give the Russians their first win in Rio.

fnatic kicked off Mirage with a pistol round win which translated to an early 4-1 lead. An Adam "⁠NEOFRAG⁠" Zouhar triple-kill kickstarted OG's own spree which eventually gave them their first lead of the map at 6-5, but mezii's men scored the next three out of four rounds to close out the half and give fnatic a narrow 8-7 advantage at the break.

Nemanja "⁠nexa⁠" Isaković's crew dropped the second pistol but won the next four straight rounds as the attackers, which put fnatic on the back seat in terms of economy and swung the momentum in OG's favor. Just as things started to look up for OG, the men in black-and-orange successfully stole the 21st round away with their full-pistol setup, which sparked a resurgence that carried on to the finish line. fnatic hit match point at 15-12 and just two rounds later wrapped the game up for a 16-13 victory, improving their Challengers Stage record to 2-0.